One method of winding a narrow strip of metal or the like on a bobbin, commonly called as traverse winding, consists of carrying on the winding while moving the bobbin or strip laterally in reciprocating traverses.
The soundness of the wound state in the traverse winding method depends on the winding conditions used. When the conditions are good, the narrow strip 1 is wound uniformly on the bobbin 2 as indicated in FIG. 5 (a). When the conditions are poor, the layered turns 1a of the strip at opposite ends on the bobbin may be depressed or collapsed as in FIG. 5 (b).
As stated above, in winding a narrow strip on a bobbin by traverse winding, inappropriate winding conditions have sometimes caused depression of the strip portions at or close to the both ends of the bobbin, leading to collapse or damage or break of the strip during winding. It has been in practice in such a situation to conduct the winding while finely adjusting the winding pitch of the strip on the bobbin. This has posed a problem of reduced efficiency of winding operation.